An Ultrasonographic Study on Correlation of Fetal Kidney Length with the Gestational Age in Third Trimester

Introduction: Accurate assessment of gestational age is pivotal to the quality of antenatal care. Failure of accurate gestational age assessment can result in iatrogenic prematurity or post-maturity, that are associated with increased perinatal mortality and morbidity. Scanty bleeding in early pregnancy and occurrence of irregular menstrual cycles in mothers on oral contraceptives may interfere with proper recording of last menstrual period, further many women in rural India fail to remember their last date of menstrual period accurately. Methods: Present study was conducted with an objective of evaluating the correlation of gestational age with the fetal kidney length in Gandhi Hospital, Musheerabad, Secunderabad from the month of July 2016 to September 2016 i. e. for a period of 3 months in which 85 pregnant ladies between age groups of 18 to 32 years were included who visited the hospital for routine antenatal ultrasound scan. All the routine fetal biometric parameters and kidney length of the fetuses were measured. Uncomplicated pregnancies, pregnancy with single fetus were included and pregnancy with multiple fetuses and all complicated pregnancies were excluded from the study. Result: The study found a strong Pearson�s correlation (r=0.52, P=0.03) for kidney length vs gestational age. Conclusion: Fetal renal lengths can aid in estimating gestational age when the other standard biometric parameters cannot be measured (low head position), or are not reliable (Eg: in IUGR abdominal circumference), if patients report in late second or third trimester when the standard fetal biometric parameters are not reliable.